Irving last played in an NBA game on March 11; he later underwent two surgeries to repair knee issues

Kyrie Irving played his last NBA game on March 11 before being sidelined with left knee pain, which ultimately required two surgeries -- the first being a removal of a tension wire, and the second to remove screws from a 2015 procedure.

After a months-long recovery process, though, Irving appears to be back at full strength. Video that surfaced on Monday shows Irving competing in a five-on-five scrimmage along with Kevin Durant, James Harden and several Miami Heat players at American Airlines Arena in Miami. It's slightly ahead of his expected recovery date, too.

Celtics GM Danny Ainge said last month that he was optimistic both Irving and his counterpart, Gordon Hayward, would be back at full strength for the start of training camp on Sept. 26, and this video all but confirms Irving's side of the bargain is being held up. As for Hayward, it's a wait-and-see approach, but Ainge indicated he could have been ready to go last month -- as could Irving, if necessary.

"I don't want to hype it up too much, but I'm saying that if our training camp were starting today that they would be here today going full speed," Ainge told ESPN on Aug. 28. "It's not like they need an extra month. I think that they know they have an extra month, so they are sort of pacing themselves. They're playing as if to build up to that opening day of training camp [Sept. 26]."

The Celtics pushed the Cleveland Cavaliers to seven games in the Eastern Conference finals without Irving and Hayward last season. With both stars back in the fold, and with LeBron James taking his talents to the West, Boston enters the 2018-19 season as the favorite to earn the No. 1 seed in the East and a prime candidate to make it to the NBA Finals for the first time since 2010.

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